I own 100 acres of property in central Ontario. In the past 26 years, I have found a total of seven [toy] balloons on my property, all of which would have had to drift for miles at least to get there, as there is no real local up wind source of balloons. The farthest was marked with the logo of a radio station in Toledo Ohio, 275 miles away, and not aligned with the prevailing winds at all.
Either my property is a statistically unusual balloon magnet, or there are a lot of balloons coming back to earth all over! So, I'll be watching for the one from Sheffield, just in case!